A pendulum consists of a ball attached to the end of a string of length l = 100 cm. The other end of the string is attached at point O1. The ball is released from rest from a horizontal position as shown in the picture. At the bottom of its swing the string hits a peg O2 a distance d = 80 cm below O1 and the pendulum continues swinging around O2 as shown by the dashed line. Treat the ball as a point object.
What is the speed V2 of the ball when it reaches a point in its swing which is level with O2?

Question

A pendulum consists of a ball attached to the end of a string of length l = 100 cm. The other end of the string is attached at point O1. The ball is released from rest from a horizontal position as shown in the picture. At the bottom of its swing the string hits a peg O2 a distance d = 80 cm below O1 and the pendulum continues swinging around O2 as shown by the dashed line. Treat the ball as a point object.
What is the speed V2 of the ball when it reaches a point in its swing which is level with O2?